The Centers for Disease Control and Prevention has sent out a warning to hospitals about a new antibiotic-resistant bacteria , carbapenem-resistant Enterobacteriaceae , or CRE . While this strain of bacteria is not new , it has become more common in the last 10 years or so and has now become prevalent enough to warrant a higher level of concern .

It 's worth backing up for a second to discuss what all of this means . We use antibiotics to treat bacterial infections . When we first started developing antibiotics , such infections were easier to cure . But over time , the bacteria evolved . They developed the ability to fight the antibiotics that we use . They pass on this ability to resist treatment to bacteria that follow . Over time , we are often forced to develop new antibiotics to beat infections that were previously treated easily .

News : CDC : ` Nightmare bacteria ' spreading

This is what has happened here with CRE . Over time , these bacteria have become harder and harder to treat . The old antibiotics do n't work as well . In this case , CRE infections kill about half of patients who have bloodstream infections . This is more than twice as many people who die from similar infections with antibiotic-susceptible strains .

Right now , CRE only are of concern to certain susceptible patients in the hospital . It 's not common in the community , and most of the warnings are directed at hospitals , imploring them to take precautions to isolate patients and prevent spread in the inpatient setting .

The nightmare scenario , though , is that this bacteria will get out into the community .

This is n't fear-mongering . Years ago , Staphylococcus aureus infections were also relatively easy to treat . Over time , though , a strain of bacteria , known as Methicillin-resistant Staphylococcus aureus , or MRSA , became a problem in hospitals . The CDC issued warnings to hospitals to take precautions to prevent its spread . Over time , though , it got out into the community .

A 2008 study of children who came into an emergency department with skin abscesses , or infections , found that about 75 % of them were caused by MRSA . Luckily , we still have medications , such as trimethoprim/sulfamethoxazole , to treat these infections . When that fails , though , things will become even more concerning .

Put another way , when I was training , we would have almost never considered MRSA as the cause of a skin infection . These days , though , we pretty much assume it 's the cause , and treat with stronger drugs .

Most people believe that the injudicious use of antibiotics is to blame for these developments . Every time we use antibiotics , we give bacteria a chance to evolve . We kill off those susceptible to the drugs and leave those that have developed resistance . Each time we use antibiotics unnecessarily , say to treat a virus , we make the problem worse . Each time we use them improperly , or for too short a period of time , we do the same . These days , we 're putting them in everything , from soap , to lotion , to the food that animals eat .

This is a real public health issue . Creating more resistant strains is a serious long-term problem . The new warning is panicking a lot of people , but for the wrong reasons . You 're very , very unlikely to get a CRE infection anytime in the near future . It 's important that hospitals work to prevent that problem from getting worse , but almost everyone reading about it this week will be unaffected by it .

It 's much , much more likely , though , that these same people will ask for antibiotics when they get a cold . That 's the kind of thing that will lead to future problems . That 's the kind of thing we need to stop now .

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Aaron Carroll says rise in drug-resistant bacteria CRE should concern us all

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He says bacterial strains -- like MSRA a few years ago -- evolve to resist antibiotics

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Concern is over spread in hospitals now , but bug could get out into community , he says

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Carroll : Misuse of antibiotics gives bacteria chance to evolve -- a real public health danger